Obesity is a disease that affects a significant portion of the world's population and leads to multiple chronic medical conditions and premature death from cardiovascular events and cancer. In particular, the United States has a current, and worsening obesity epidemic. The U.S. Centers for Disease Control and Prevention (CDC) reports that over 33% of the U.S. population is obese, with a Body Mass Index (BMI) of over 30, and another 35-40% of the US population is overweight, with a BMI of 25-30. The CDC reports that the percent of the US population being either overweight or obese by 2018 will be 75%. The CDC also reports that obesity directly costs the U.S. economy $147 billion currently, and projects that the costs will approach $315 billion by 2020.
Further, obesity has environmental, genetic and behavioral origins but is intractable to most medical and behavioral interventions. To help reduce obesity and/or facilitate weight loss, bariatric surgery may be an option for some patients that may be overweight. Typically, bariatric surgery may be an effective long-term treatment option for patients with a BMI greater than 35. Despite the 20 million patients who are eligible for weight loss surgery in the U.S., the number of procedures per year has plateaued at about 200 thousand, eliminating any public health effect of surgery.
In recent years, a popular form of bariatric surgery may include a laparoscopic vertical sleeve gastrectomy (e.g., which may remove approximately 80% of the stomach). Laparoscopic vertical sleeve gastrectomy may be a procedure that may be safer and more effective for patients eligible for weight loss surgery. In fact, it has been accepted as the surgery that should be offered to most morbidly obese patients over, for example, laparoscopic adjustable gastric banding and laparoscopic Roux-en-Y gastric bypass. As such, the surgery has been adopted by bariatric surgeons and is now the most commonly performed weight loss surgery.
Vertical sleeve gastrectomy is typically performed using standard laparoscopic equipment. The greater curvature of the stomach is mobilized using vessel-sealing devices, sealing the gastric branches of the gastroepiploic vessels and the short gastric vessels. The posterior adhesions of the stomach are also divided so the stomach is fully mobilized while the blood supply to the lesser curvature remains intact.
Following mobilization of the stomach a calibration tube is typically introduced into the stomach through the mouth. Resection is accomplished by applying a series of staples from a laparoscopic linear surgical stapler, for example, along the calibration tube in a staple line. The staple line may be important in sleeve gastrectomy as the amount of weight lost and complications or consequences may be a direct result of the quality of the resultant sleeve gastrectomy pouch formed from the staple line (e.g., the portion of the stomach not rescinded by the staple line). The complications or consequences may include gastroesophageal reflux disorder (GERD), weight loss failure or weight regain, food intolerance, staple line bleed, leak, and/or the like.
To perform the sleeve gastrectomy and produce sleeve gastrectomy pouch (e.g., from the staple line), a sleeve gastrectomy stapling guide and a catheter or tube may be used. Although the combination of the stapling guide and catheter or tube may help produce a better staple line, a surgeon may still need to estimate or envision an adequate distance to form the sleeve gastrectomy pouch with a suitable volume, shape, and/or size. To help improve the volume, size and/or shape of the sleeve gastrectomy pouch, the surgeon may want to measure volume of the sleeve gastrectomy pouch prior to stapling. Unfortunately, currently, the volume may be measured in follow ups after the sleeve gastrectomy may have been performed to diagnose problems that may have occurred and/or determine why the sleeve gastrectomy may not have been successful. Further, other surgical weight loss procedures such as vertical banded gastroplasty that may provide techniques and/or devices to measure volume of a pouch prior to placing a band at the area of the stomach the surgeon wishes to remove as part of the pouch may not be suitable for use in a sleeve gastrectomy. For example, those current techniques may not provide a stapling guide that may be long enough to occlude the length necessary to produce the staple line in a sleeve gastrectomy and also may not provide devices and/or techniques to occlude the esophagus and the pylorus to pressure the sleeve gastrectomy pouch necessary to measure its volume.